Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Aeroacoustics effects of the Wavy Leading Edge on a Fan-Rig SDT stators.
Submission Author:
Andressa Garcia , SP
Co-Authors:
Andressa Garcia, Hernán Cerón-Muñoz, Rolando Guzmán-Bohórquez
Presenter: Andressa Garcia
doi://10.26678/ABCM.COBEM2023.COB2023-0411
Abstract
In recent decades, noise from aircraft engines has been reduced considerably due to by-pass technology, and fan noise has become predominant. The interaction between the turbulent wake of a rotor and the stator vanes has been identified as one of the main sources of broadband noise, in addition to tonal noise. Studies inspired by the silent flight of the owl have shown that the application of certain natural properties of its wings, such as the serrated pattern on the leading edge (WLE), are effective techniques for reducing aeronautical noise. This work aimed at the explanatory study of these characteristics applied to the stator vanes Source Diagnostic Test (SDT) Low-Noise model of the Rig-Fan aeroacoustic tunnel at EESC/USP. The geometry of the vanes was defined according to the literature and printed for the experimental tests and the performance of the noise emission analysis. Data acquisition is obtained with the acoustic instrumentation of the bench, using 9 microphones positioned in rings in the duct, for the standard (Low-Noise) and new model (WLE) stator. For data processing, the Welch method is used to obtain the spectra in Sound Pressure Levels (SPL). The tests were performed with rotor speeds from 800 to 1800 rpm for both stator. The acoustic measurements of the WLE stator when compared to the Low-Noise stator had a reduction of 1.5 to 4 dB in low and medium frequencies, while there was an increase in high frequencies of up to 1.2 dB. Insignificant changes were found in noise levels when the flow rate was reduced (throttle). It is understood by this study that there is no ideal serration that reduces noise for all types of conditions that are imposed, but it is more efficient at low rotation speeds, which could be used to improve the approuch or take-off conditions of aircraft.
Keywords
Wavy Leading Edge, SDT, Reduction Noise, Rig Fan
